Atmospheric pressure depends on the altitude (or height) of your location. How should air pressure change if you are in Denver, Colorado, which is 1.5 kilometers (1 mile) above sea level?

Air Pressure Decreases with increasing altitudes. The gravitational attraction between the earth and air molecules is greater for those molecules nearer to earth than those further away. At higher altitudes, there fewer air molecules.

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"